Seed fungicide treatment for wheat
The office has been busy taking in 4-H entry forms for the Delaware County Fair. Our Fair will open on September 17th, which is just three weeks away. We have been gearing up for a few weeks now. The weather is feeling more “fall like” and it reminds us that fall is clearly around the corner. Forecasters are calling for near normal temperatures and below normal rainfall for these next two weeks.
Seed Fungicide Treatment for Wheat
Seed fungicide treatments may prevent early establishment of diseases such as Stagonospora blotch and minimize problems with loose smut and common bunt. It could also play an important role in giving seedlings a good head start by protecting them from early-season diseases caused by Fusarium, Pythium, and Rhizoctonia species. Pierce Paul, OSU Extension Specialist in Plant Pathology says that seed treatments are most beneficial for seeds infected prior to planting or when seeds are planted under cool, wet soil conditions. However, seed treatments should not be considered a cure-all for the selection of poor seed lots. They will not increase the germination of poor quality seeds â€“ seeds with excessive mechanical damage, seeds stored under poor conditions, genetic differences in variety, or other damage.
Seed treatments do not always increase yield, but in general, seed treatments result in increased yield by minimizing stand reduction resulting from infection and death of seedlings caused by soil borne pathogens. According to Paul, protection is also short-lived, generally only lasting as long as it takes for the crop to emerge. In addition, no single seed treatment or active ingredient is equally effective against all soil borne pathogens or all populations of the same pathogen. “Producers should select seed treatment based on potential seed and seedling disease problems and the history of such problems in their fields.”Paul said. For instance, avoid planting seeds harvested from scab-infected fields, but if scabby seeds are used for planting, then a fungicide with activity against Fusarium should be selected. On the other hand, if a field has a history of Pythium damping off due to cool, wet planting conditions, a seed treatment product with activity against Pythium should be selected.
It is highly recommended that winter wheat seeds be treated for control of several seed-borne diseases, including loose smut, common bunt, Stagonospora glume blotch and scab. According to Paul, the systemic fungicides Dividend Extreme and Raxil — Thiram, and Raxil XT have excellent activity against both loose smut and common bunt at low usage rates (a.i./ cwt). Dividend Extreme is effective in controlling seed-borne Stagonospora, but it is more effective against seed-borne scab at the higher rate (1.0 fl. oz./cwt) than at the lower rate (0.5 fl. oz./cwt). In general, triazole-based fungicide such as Raxil and Charter, used at the labeled rates, are effective against seed-borne Stagonospora and have relatively good activity against seed-borne scab. Products with Metalaxyl and Mefenoxam are effective against Pythium. “For best results and protection against a wide range of pathogens, seeds should be treated with multiple active ingredients,” Paul said.
Visit the field crops disease website for more on wheat seed treatment: oardc.ohio-state.edu/ohiofieldcropdisease/images/Wheat_seed_ treatment_chart_2010_rev_10_28_2010.pdf.
Rob Leeds is the OSU Extension Educator for Delaware County.